Purpose: To move air in a room.
Issue: The motors in the fans generate electrical and magnetic fields. These fields can penetrate walls and ceilings and effect health.
Better Choice: Usually, ceiling fans are high enough up, and the fields disspiate enough that being in a room sitting below them is not an issue. However, if you are sitting or sleeping ABOVE a ceiling fan, you may want to use your meters to make certain it is safe and that you are a safe distance from them.